CN116060743A - Spiral welded steel pipe forming and welding control method and system - Google Patents
Spiral welded steel pipe forming and welding control method and system Download PDFInfo
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- CN116060743A CN116060743A CN202310141935.0A CN202310141935A CN116060743A CN 116060743 A CN116060743 A CN 116060743A CN 202310141935 A CN202310141935 A CN 202310141935A CN 116060743 A CN116060743 A CN 116060743A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/18—Submerged-arc welding
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K33/00—Specially-profiled edge portions of workpieces for making soldering or welding connections; Filling the seams formed thereby
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/32—Accessories
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Abstract
The invention provides a method and a system for controlling the forming and welding of a spiral welded steel pipe, which relate to the technical field of welding control, and aim at solving the problems of poor welding stability and high energy consumption caused by poor adjustment efficiency in the control and adjustment process of submerged arc welding of the existing welded steel pipe.
Description
Technical Field
The invention relates to the technical field of welding control, in particular to a method and a system for controlling the forming and welding of spiral welded steel pipes.
Background
The anticorrosive steel pipe is used as a conveying channel in a large amount, and in the whole steel pipe product sequence, the pipe with the caliber DN of more than 300mm is mainly a spiral steel pipe. The spiral steel pipe is formed by taking a steel belt or a steel plate as a raw material, rolling the steel belt or the steel plate into a shape through a spiral unit, and performing on-line welding, hydraulic pressure detection, X-ray detection or ultrasonic detection, repairing, flat-head chamfering and other procedures. The pipe has the advantages of low cost, high safety coefficient, high production efficiency and the like, and is widely popularized and applied in the industry.
Although the current spiral steel pipe production line has higher upgrading speed and higher automation degree, the main link which is restricted in production and is difficult to solve at present is a submerged arc welding process. The submerged arc welding is adopted, real-time adjustment is needed during production according to the welding state, the raw material state and the like, but the current adjustment mode is mostly dependent on the operation of welding personnel, is greatly influenced by human factors, and although a plurality of related control adjustment methods are disclosed in the prior art, the real-time adjustment efficiency is poor during the correction process, and the problems of poor welding stability and high welding energy consumption exist, so that the production efficiency and the product quality are seriously restricted.
Disclosure of Invention
Aiming at the defects existing in the prior art, the invention provides a spiral welding steel pipe forming welding control method and a system, which are used for determining welding parameters and continuously correcting parameter values in the welding process by effectively combining the welding experience value, heat conversion efficiency, welding actual parameters and characteristics of welding appearance gears and performances, are used for guiding and applying actual production, improving welding stability and reducing welding energy consumption.
The first object of the invention is to provide a spiral welded steel pipe forming welding control method, which adopts the following scheme:
calculating the sectional area of the welding seam according to the shape of the welding seam, and calculating the theoretical heat required by welding seam melting by combining the welding speed and the parameters of the steel pipe;
setting welding current and welding voltage, obtaining welding energy, and comparing the welding energy with theoretical heat;
when the ratio of the welding energy to the theoretical heat is not in the set range, the welding current and the welding voltage are adjusted until the arrangement of the welding energy and the theoretical heat is in the set range.
Further, the width and depth of the weld are determined according to the wall thickness of the welded steel pipe and the raw material specification, so that the shape of the weld is determined to calculate the sectional area of the weld.
Further, the depth of the weld seam is the penetration of a molten pool during welding, the size of the weld seam is smaller than the wall thickness of the steel pipe to avoid burn-through, and the wall thickness of the steel pipe is larger than or equal to 0.6 times to ensure the welding strength of the steel pipe.
Further, calculating the theoretical heat required for melting the weld includes the steps of:
obtaining the temperature difference from the initial temperature to the welding melting temperature of the steel pipe;
calculating the weight of the weld joint area in unit length based on the sectional area of the weld joint, the welding speed and the welding wire density;
the theoretical heat required for melting the weld is calculated by combining the temperature difference and the weight of the weld area.
Further, the density of the welding wire is consistent with the density of the steel pipe.
Further, an effective coefficient of the welding power is set, and the effective coefficient is in a value range of 0.75-0.85.
Further, when the welding current is regulated, the minimum value of the acquired correction range is sequentially selected upwards until the welding energy requirement is met.
Further, the welding current value is determined according to the wall thickness of the steel pipe, the diameter of the welding wire and the combination of empirical values.
Further, the welding voltage value is determined based on the welding current and the wire diameter coefficient.
A second object of the present invention is to provide a spiral welded steel pipe forming welding control system comprising:
a theoretical data acquisition module configured to: calculating the sectional area of the welding seam according to the shape of the welding seam, and calculating the theoretical heat required by welding seam melting by combining the welding speed and the parameters of the steel pipe;
a comparison module configured to: setting welding current and welding voltage, obtaining welding energy, and comparing the welding energy with theoretical heat;
an adjustment module configured to: when the ratio of the welding energy to the theoretical heat is not in the set range, the welding current and the welding voltage are adjusted until the arrangement of the welding energy and the theoretical heat is in the set range.
Compared with the prior art, the invention has the advantages and positive effects that:
(1) Aiming at the problems of poor welding stability and high energy consumption caused by poor regulation efficiency in the control regulation process of submerged arc welding of the existing welded steel pipe, the welding parameters are determined and continuously corrected in the welding process by effectively combining the characteristics of the welding experience value, the heat conversion efficiency, the welding actual parameters, the welding appearance gear and the performance, so that the welding stability is improved and the welding energy consumption is reduced.
(2) And carrying out correction by taking the welding parameter value into the formula, and sequentially and upwards selecting the welding current from the minimum value until the requirement is met, so that the requirements of the penetration and the width of a molten pool during welding can be met, a welding seam meeting the requirements of strength and form can be formed, and the welding energy consumption can be reduced by reducing the welding current.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention.
FIG. 1 is a schematic cross-sectional view of a submerged arc welded seam in example 1 of the present invention.
Detailed Description
Example 1
In an exemplary embodiment of the present invention, as shown in fig. 1, a method for controlling the forming welding of a spiral welded steel pipe is provided.
In the current spiral steel pipe production line, steel strips or steel plates are used as raw materials, are welded after being rolled and formed by a spiral unit, submerged arc welding is adopted, real-time adjustment is needed according to the welding state, the raw material state and the like, but the current adjustment mode is mostly dependent on the operation of welding personnel, is greatly influenced by human factors, and although some related control and adjustment methods are disclosed in the prior art, the real-time adjustment efficiency is poor in the correction process, and the problems of poor welding stability and high welding energy consumption exist.
Based on the above, the embodiment provides a spiral welded steel pipe forming welding control method, which effectively combines the characteristics of welding experience value, heat conversion efficiency, welding actual parameters, welding appearance gears and performances, determines the welding parameters and continuously corrects the parameter values in the welding process, is used for guiding and applying actual production, improves welding stability and reduces welding energy consumption.
The method for controlling the formation and welding of the spiral welded steel pipe will be described in detail with reference to the accompanying drawings.
Referring to fig. 1, based on the forming principle of the spiral steel pipe, the forming speed and the welding speed of the weld joint are subjected to data correlation; combining a welding principle with the geometric dimension of the welding seam, and calculating the welding filling quantity according to a mass conservation principle; combining with the actual energy conversion efficiency on the basis of mass conservation, and calculating the total energy demand by utilizing the specific heat capacity of the steel pipe; according to actual welding experience and welding requirements, the form required by welding is fixed, data measurement is carried out through a sensor, and measured data can be transmitted.
And by combining the data, a welding parameter calculation model is established, and the purpose of automatic control of the welding process parameters of the spiral welding steel pipe molding is realized. And the automatic welding parameter and the stable welding quality are achieved.
In the process of spiral welding of a steel pipe, important parameters of a welding process comprise welding current and welding voltage, wherein the welding current is represented by I1, and the welding voltage is represented by V1; the direct factors influencing the forming welding process are mainly forming speed, steel plate thickness, groove angle, welding wire diameter and the like.
The process parameters known in actual production include: the steel tube comprises a steel tube outer diameter (D0), a steel tube wall thickness (T), a steel tube density (rho 1), a steel tube initial temperature (T1), a steel plate progressive speed (v 3), a welding wire diameter (D1), a welding wire density (rho 2), a welding seam required width (B1), a welding seam excess height (h 1) and a welding melting temperature (T2).
Wherein, the required width B1 of the welding seam is 10mm, and the residual height h1 of the welding seam is 2.5mm.
The unknown technological parameters in actual production include: welding current (I1), welding voltage (V1), welding section area (S1), welding speed (V2), welding power (P), welding power effective coefficient (eta), welding demand theoretical heat (Q), welding time (t 2), total welding weight (M), welding weight (M1) and specific heat capacity (ρ) of the steel plate.
The outer diameter of the steel pipe, the wall thickness of the steel pipe, the density of the steel pipe and the density of the welding wire are known parameters;
the temperature difference between the initial temperature T1 and the welding melting temperature T2 of the steel pipe: Δt=t2-T1;
the steel pipe is heated to a welding melting temperature T2 at an initial temperature, and the required energy is as follows: q=mΔt;
welding power effective coefficient eta is 0.75-0.85 in combination with practical production experience;
welding power: p=i1×v1.
Determining welding parameters conforming to actual production by utilizing the data is the basis of a welding control method, wherein the relation between the current and the voltage in the welding process is a rule obtained by combining theoretical calculation with the actual production condition; the method can be used for guiding the production to control and adjust the parameters of the total welding power, the actual current and the actual voltage by the difference between the total required energy of the welding line and the actual welding energy in the forming welding process.
The theoretical calculation is combined with the actual welding condition to correct the welding parameters, so that the purpose of real-time adjustment is achieved. In this embodiment, the method for controlling the forming welding of the spiral welded steel pipe includes:
calculating the sectional area of the welding seam according to the shape of the welding seam, and calculating the theoretical heat required by welding seam melting by combining the welding speed and the parameters of the steel pipe;
setting welding current and welding voltage, obtaining welding energy, and comparing the welding energy with theoretical heat;
when the ratio of the welding energy to the theoretical heat is not in the set range, the welding current and the welding voltage are adjusted until the arrangement of the welding energy and the theoretical heat is in the set range.
The welding line shape is determined according to the wall thickness of the welded steel pipe and the specification of raw materials so as to calculate the sectional area of the welding line, and different welding widths and depths are configured for the raw materials with different specifications, so that the welding line has different sectional areas of the welding line.
In this embodiment, the weld depth is the penetration of the molten pool during welding, the size of the weld pool is smaller than the wall thickness of the steel pipe to avoid burn-through, and the wall thickness of the steel pipe is greater than or equal to 0.6 times to ensure the welding strength of the steel pipe.
According to the molding principle: v3=v2. The penetration H and the welding current I1 are in a linear relation: h=k/100×i1; the value of k is generally 1.1 in combination with experience.
In combination with experience, welding current i1=40×t+50d1+50; welding voltage v1=30+i1/100+c, where C is the wire diameter coefficient; the welding penetration is not less than 0.6 time of the wall thickness of the steel pipe, namely H is more than or equal to 0.6t and less than or equal to 0.7t; the weld cross-sectional area S1 is shown in FIG. 1. In addition, welding current i1=28 (t+10) and welding voltage v1=0.5t+30 may be configured.
The configuration experience parameters are shown in table 1:
TABLE 1 welding currents for different diameter welding wires
C is 1 when the welding wire phi is 5 mm; c is 2 when the welding wire phi is 4 mm; and C is 2 when the welding wire phi is 3 mm.
And determining the welding penetration according to the time production experience parameters, wherein the width and the height of the welding seam are actual measurement values, and in addition, the actual temperature measurement value of the welding melting temperature liquid level is not a calculated value and needs to be adjusted according to the welding melting temperature.
Total weight of weld zone m=s1×v2×ρ1; the density of the welding wire is consistent with that of the steel plate;
theoretical heat required for weld melting q=mΔt=ρ×s1×v2×t2×ρ1×Δt;
welding power: p=i1×v1; and p×t2×η=q, i.e.: i1×v1×t2=ρs1×v2×t2×ρ1×Δt; i1×v1=ρs1×v2×ρ1×Δt;
welding current i1=h/k×100; i1 =40×t+50d1+50; then: h/k=40×t+50d1+50; combining actual production experience k to take the value of 1.1, and taking the value of H to 0.6t and 0.7t respectively;
the wire diameters are respectively: d1 = (14.5 t-50)/50 and d1= (23.6 t-50)/50;
welding current: i1 =h/k100=54.5 t-63.6t;
wherein the diameter of the welding wire is taken among four values of 3, 4, 4.5 and 5. In addition, the welding current is generally selected to be smaller in value, so that energy consumption can be reduced.
Welding voltage: v1=30+i1/100+c; the voltage value is v1=30+0.545t+c/30+0.636t+c;
after the welding current and the welding voltage are determined, the welding power is as follows: p=i1×v1;
namely: p= (30+i1/100+c) I1; welding energy q1=pxt2= (30+i1/100+c) xi1x t2
And according to the effective efficiency eta of the welding energy Q1 is more than or equal to the theoretical heat Q required by the welding line melting; in combination with actual welding experience, the effective efficiency eta < (1+0.15) of the welding energy Q1 is the theoretical heat Q required by the welding line melting.
Then: then: 1.15 ρ 1 v2 ρ1 Δt Σ (30+i1/100+c) i1 η Σ ρ1 v2 ρ1 Δt; the welding parameter values are therefore brought into the formula for correction, and the welding current is successively selected upwards from the minimum value until the requirement is met.
For example: when the pipe with the wall thickness of 10mm is welded, the width of the welding line is 10mm; the temperature at which the steel is welded averages t2=6500 ℃; ambient temperature t1=25 ℃; the specific heat capacity of the steel is 480J/(kg. DEG C); the density of the steel is 7.85g/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the Welding cross-sectional area s1=42 mm 2 The method comprises the steps of carrying out a first treatment on the surface of the Welding speed v2=1.2 m/min, so the weld meltsTheoretical heat required q= 122.96J/mm 2 ；
In combination with the first empirical formula: welding time t2=1/V2, current I1 takes on a value between 545-636, first takes on a value 545, then takes on a value 2, then v1= (30+i1/100+c) =37.45, η takes on a value 0.8; welding energy Q1 effective efficiency η= 136.06J/mm 2 ；1.15*122.96J/mm 2 ≥136.06J/mm 2 ＞122.96J/mm 2 The method comprises the steps of carrying out a first treatment on the surface of the So current value 545 and voltage value 37.45 can meet a welding speed of 1.2m/min. In combination with the second empirical formula: i1 =560, v1=35; welding energy Q1 effective efficiency η= 130.66J/mm 2 ；1.15*122.96J/mm 2 ≥130.66J/mm 2 ＞122.96J/mm 2 The method comprises the steps of carrying out a first treatment on the surface of the So the current value 560 and the voltage value 35 can meet the welding requirement; combining two empirical formulas, and taking 545-560 current process parameter values; the voltage process parameter value is 35-37.5. The welding parameters are shown in table 2.
Table 2 data comparison
The system adjusts the current and voltage through the continuous input correction of the current in the welding process; the welding quality is ensured to be stable in the process of combining actual welding, and meanwhile, the current value is sequentially increased and adjusted according to the minimum requirement, so that the energy-saving effect can be achieved.
Example 2
In another embodiment of the invention, a spiral welded steel pipe forming welding control system is provided.
Comprising the following steps:
a theoretical data acquisition module configured to: calculating the sectional area of the welding seam according to the shape of the welding seam, and calculating the theoretical heat required by welding seam melting by combining the welding speed and the parameters of the steel pipe;
a comparison module configured to: setting welding current and welding voltage, obtaining welding energy, and comparing the welding energy with theoretical heat;
an adjustment module configured to: when the ratio of the welding energy to the theoretical heat is not in the set range, the welding current and the welding voltage are regulated until the arrangement of the welding energy and the theoretical heat is in the set range
It will be appreciated that the working method of the above spiral welded steel pipe forming and welding control system is the same as that provided in embodiment 1, and reference may be made to the detailed description in embodiment 1, and the details are not repeated here.
The above description is only of the preferred embodiments of the present invention and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A spiral welded steel pipe forming welding control method is characterized by comprising the following steps:
calculating the sectional area of the welding seam according to the shape of the welding seam, and calculating the theoretical heat required by welding seam melting by combining the welding speed and the parameters of the steel pipe;
setting welding current and welding voltage, obtaining welding energy, and comparing the welding energy with theoretical heat;
when the ratio of the welding energy to the theoretical heat is not in the set range, the welding current and the welding voltage are adjusted until the arrangement of the welding energy and the theoretical heat is in the set range.
2. The method for controlling the forming welding of spiral welded steel pipes as claimed in claim 1, wherein the width and depth of the weld are determined according to the wall thickness of the welded steel pipes, the specification of raw materials, thereby determining the shape of the weld to calculate the sectional area of the weld.
3. The method for controlling the forming welding of spiral welded steel pipes as claimed in claim 2, wherein the depth of the weld is the penetration of the molten pool during welding, the size of the weld is smaller than the wall thickness of the steel pipe to avoid burn-through, and the wall thickness of the steel pipe is greater than or equal to 0.6 times to ensure the welding strength thereof.
4. The method of controlling the forming welding of a spiral welded steel pipe according to claim 1, wherein calculating the theoretical amount of heat required for melting the weld joint comprises the steps of:
obtaining the temperature difference from the initial temperature to the welding melting temperature of the steel pipe;
calculating the weight of the weld joint area in unit length based on the sectional area of the weld joint, the welding speed and the welding wire density;
the theoretical heat required for melting the weld is calculated by combining the temperature difference and the weight of the weld area.
5. The method of controlling the forming welding of a spiral welded steel pipe according to claim 1, wherein the density of the welding wire is identical to the density of the steel pipe.
6. The welding control method for forming a spiral welded steel pipe according to claim 1, wherein an effective coefficient of the welding power is set, and the effective coefficient has a value ranging from 0.75 to 0.85.
7. The welding control method for forming a spiral welded steel pipe according to claim 1, wherein when the welding current is adjusted, the minimum value of the obtained correction range is sequentially selected upward until the welding energy requirement is satisfied.
8. The method of controlling the forming welding of a helically welded steel pipe of claim 1, wherein the welding current value is determined based on the wall thickness of the pipe, the diameter of the wire, and an empirical value.
9. The welding control method for forming a spiral welded steel pipe according to claim 8, wherein the welding voltage value is determined according to a welding current and a wire diameter coefficient.
10. A spiral welded steel pipe forming welding control system, comprising:
a theoretical data acquisition module configured to: calculating the sectional area of the welding seam according to the shape of the welding seam, and calculating the theoretical heat required by welding seam melting by combining the welding speed and the parameters of the steel pipe;
a comparison module configured to: setting welding current and welding voltage, obtaining welding energy, and comparing the welding energy with theoretical heat;
an adjustment module configured to: when the ratio of the welding energy to the theoretical heat is not in the set range, the welding current and the welding voltage are adjusted until the arrangement of the welding energy and the theoretical heat is in the set range.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116551238A (en) * | 2023-07-12 | 2023-08-08 | 苏州友得利金属制品有限公司 | Welding process control method and system for galvanized steel pipe |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116551238A (en) * | 2023-07-12 | 2023-08-08 | 苏州友得利金属制品有限公司 | Welding process control method and system for galvanized steel pipe |
| CN116551238B (en) * | 2023-07-12 | 2023-10-20 | 苏州友得利金属制品有限公司 | Welding process control method and system for galvanized steel pipe |
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